By charting the slopes and crags on animals’ teeth as if they were mountain ranges, scientists at the Smithsonian’s National Museum of Natural History have created a powerful new way to learn about the diets of extinct animals from the fossil record.

Understanding the diets of animals that lived long ago can tell researchers about the environments they lived in and help them piece together a picture of how the planet has changed over deep time. The new quantitative approach to analysing dentition, reported on 21 November in the journal Methods in Ecology and Evolution, will also give researchers a clearer picture of how animals evolve in response to changes in their environment.

A 3D reconstruction of the teeth of a western gorilla (Gorilla gorilla).